Bituminous protective compositions



arsnip Endive Patented Aug. 14, 1945 2,382,331 BITUDIINOUS PROTECTIVE COMPOSITIONS Harold Schiller, Los Angeles, Calii'., assignor to Socony-Vacuum Oil Company, Incorporated,

New York,

N. Y., a corporation of New York No Drawing. Application June 1, 1943, Serial No. 489,298

(Cl.10.618) 7 g The object gf ti e i tion is to prov'ddakcadmiumemercury;chr m nickel 4 Claims.

method for protecting articles made of vegetable fibre-nets, rope, twine, thread, lines and loosely woven fabricsfrom the combined effects of bacterial rotting, abrasion and exposure to sunlight.

It is old practice to saturate fishing nets and similar articles with hot wood tar or coal tar. This treatment i effective in increasing the resistance to wear and to-the effects of sunlight but has relatively little bactericidal effect. It is undesirable as greatly increasing the weight of r the article, often by as much as 100 percent, and

in making it still and difllcult to handle.

Such tars have also been used in the form of solutions in volatile solvents, with much the same final results and with added cost and hazard incident to the evaporation of expensive and usually inflammable. solvents. v

Another treatment which has been proposed and which is effective against bacterial action is to saturate the net or other fibrous article with a solution of copper soap in naphtha or in dilute ammonia. This treatment offers very little protection against wear or the deleterious effects of the ultra-violet constituent of sunlight and the copper soap films deteriorate rapidly on contact with sea water.

I propose to combine and greatly to facilitate the application of these two treatments and at the same time materially to prolong the useful life of the bactericide, by immersing the nets or other articles in an aqueous emulsion having tar or asphalt as the dispersed phase and a soap of a bactericidal metal in either the dispersed 1r the continuous phase according to the manner in which the treating liquid is prepared.

The bituminous constituent: of the treating liquidmay 'be a reduced wood tar or coal tar or a soft asphalt. An asphalt produced by the steam reduction of Pacific Coast or Gulf Coast petroleum to apenetration ranging from 75 to 100 at 77 F. is preferred for most purposes. Asphalts which are too hard reduce the pliability of the treated article-while those which are too soft are liable to render it sticky. The penetration of the asphalt may be adjusted to meet climatic conditions and the penetration range stated is to be considered as suggestive only. i

It is an advantage of the general method herein described that it permits the readily available petroleum a phalts to be substituted, without loss of efllciency,

ways more refractory wood or coal tars.

. The metal soap may be a salt of copper, zinc,

for the often more costly and alsilver with naphthenic acids, resin acids or fatty acids such as oleic, stearic, lauric and palmitic. These metals may be described generically as the toxidheavy metals while the acids may be' referred to generically as soap-forming organic acids. Both the soap and the asphalt are substantially insoluble in water but are subject to aqueous emulsification. The soap only may be brought into aqueous solution by the use of ammonia or an amine, with or without the addition of a water-miscible solvent. In such solution the soap is an effective emulsifying agent for asphalt.

The soap and the asphalt are mutually soluble at a temperature at which the asphalt is entirely fluid. Finally, either the asphalt alone or the blend of asphalt and soap is subject to emulsification in a variety of well known ways, some of which will be described. I

The recital .of these properties points to two basically distinct methods for preparing the aqueous treating agent, viz:

Method 1.-The soap may be brought into aqueous solution by the addition of ammonia or of a volatile amine and this solution mixed with a previously prepared aqueous emulsion of the ashalt; p Method 2.The soap may be dissolved in the asphalt and the blend then emulsified with water containing ammonia ora volatile amine.

The distinction between these two methods, as regards the final result, is that in the first named the soap is carried in the aqueous phase and is precipitated on the surface of'the fibre as thesolubilizihg'agent (ammonia or amine) evaporates, while in the second the soap is partially carried in the bituminous phase and is precipitated with the asphalt when the emulsion breaks on contact with the surfaces of the fibres. The first method tends'to enhance the bactericidal protection afforded by a given quantity oi the toxic metal soap; the second to prolong the useful life of the soap at the expense of a reduction in its momentary activity.

In the application of method 1 above to the preparation of the treating liquid I proceed as follows:

(a) To a body of water is added ammonia or a water-soluble amine of reasonably rapid evaporation rate (preferably boiling above 15 C. and

below "(2.) and which iscapable of forming a complex with the metallic ions of the soap in be'used. Mono-, .diand triethylamine, normal and isopropylamine and the three butylamines are suitable for this use and may be referred to generically as volatile aliphatic amines. While fully functional, there is no advantage in the substitution of the more costly amines for ammonia other than, insome instances, to slow down the precipitation of the soap which follows from evaporation of the solubilizing agent.

(b) The metal soap may be prepared in advance, by any of the conventionai'methods, or may be formed in situ. In the first case the soap may be dissolved in the ammonia or amine solution by prolonged contact or, more readily, by prior solution in a water-miscible solvent such as isopropyl or butyl alcohol. In the second case a water-soluble salt of the metal is added to the ammonia or amine solution to produce a metalloamine complex, after which the organic acid is added.

An aqueous emulsion of the asphalt is prepared in any conventional manner, preferably by a method which produces an emulsion which does not break too rapidly. For example, a thin stream of the molten asphalt may be introduced,

with strong agitation. into a hot aqueous solution containing from 0.5% to 2.0% oleate. The agitation is continued after the addition of the asphalt, if necessary, until the bitumen is completely and finely dispersed and the emulsion assumes a light brown color. The fin ished emulsion may contain more or weight of asphalt, though this figure is far from critical. The ammonia soaps are preferred over the potassium or sodium soaps as they leave a residue which is free from tendency to re-emulsify. Any of the stabilizing agents of the prior art may be added to enhance the keeping quality of the emulsion if it is not to be used immediately. Casein or other protein is suitable for this purpose.

(d) The soap solution produced in step lb) and the emulsion produced in step K6) are then mixed in such proportions as to obtain the desired relation of metal to bitumen 2n the treating liquid. The following examples are typical of the above procedure:

Example 1.-Soap previously prepared To a solutionof 100 parts aqueous ammonia 28% NHi) in 500 parts of water were added 100 parts of a solution of copper naphthenate in :sopropyl alcohol. the concentration of this solution being equal to 9% copper content.

To this solution were added 200 parts of an aqueous emulsion of an 80/90 penetration asphalt Copper naphthenate per cent..- 8.8 40.8 Asphalt do 12.? 58.3 Ammonium oleate do 0.1 0.4 Isopropyl alcohol do 2.3

Casein s Trace Ammonia as NH: "per cent 3.1

Water 4 do 72.0

This or any other of the products of the examples may be further diluted with water if required.

of ammonium less by 1 Lil) corporated in Example 2.-Soap prepared in situ Copper oleate per cent" 14.0 44.3 Asphalt ..do 14.5 45.9 Ammonium sulfate do 3.1 9.8 Ammonia as NH: do- 1.4 Water do 67.0

Example 3.-Sepa1"ate emulsification To a solution of n-propylamine parts in 450 parts of water were added parts of a solution of zinc oleate in a volatile petroleum solvent containing 8% of zinc. The mixture was agitated until the petroleum solution was intimately dispersed in the amine solution. This dispersion was mixed with 200 parts of a soap-stabilized asphalt emulsion containing 45% of 80/90 penetration asphalt. The percentage composition of this product, before and after the evaporation of the volatile components. is as follows:

Zinc oleate per cent 13.3 56.3 Asphalt do.. 10.0 42.4 Ammonium oleate do 0.3 1.3 ietroleum solvent d0 3.4 Propylamine do.. 11.2 Water ..do 61.8

of method 2 to the preparaliquid the procedure is as In the application tion of the treating follows:

(e) An aqueous solution of ammonia or an amine is prepared as in (a) above;

(I) The asphalt is heated to a temperature at which it is completely fluid, as for example about 212 Fahn, and the soap blended with it. If the soap contains much water it will be necessary to use a slightly higher temperature and continue heating until the soap is at least partially dehydrated. permitting it to pass into solution in the asphalt;

(g) The asphalt-soap blend is then emulsified with a relatively small quantity of water containme either a preformed soap or a relatively nonvolatile amine. In the latter case a corresponding quantity of a soap-forming fatty acid is inthe blend (1) of asphalt and toxic metal soap. As this step of emulsiiication is nee essarily performed at atemperature close to the boiling point of water, the use of ammonia or of a volatile amine will be found wasteful unless the emulsiflcation is performed in a closed system:

(h) The concentrated emulsion produced in .(g) is cooled to more or less atmospheric temperature and blended with such quantity of the ammonia or amine solution (e) as may berequired to give the dilution desired for use.

Example 4.--Using preformed soluble soap 100 parts of 80/90 penetration asphalt were heated to 200 Fahr. and blended with 200 parts of zinc naphthenate previously prepared from naphthenic acids of an average molecular weight of 250. The blend was then emulsified, by agitation at about -200 Fahn, with 200 parts of a 1% aqueous solution of ammonium oleate, giving a concentrated fine dispersion. This product was cooled to about 80 Fahr. and blended with a solution of 100 parts 28% aqueous ammonia with 400 parts water. The percentage composition of this product, before and after evaporation, is as follow:

,, Zine naphthenate per cent 20.0 66.2 AsphaltILQx; er. do 10.0 33 .1 Ammonium oleate :do; n.0 .2 0.7 Ammonia as NHa do 2.8--- Water do 67.0

Example 5.Using soap-forming constituents molten mixture was then added, with strong agitation, to a boiling solution of 5.5 parts triethanolamine (boiling point 277 C. at 155 mm.) in 200 partswater. The product was a finely dispersed concentrate which, after cooling, was blended with a solution of 80 parts 28% aqueous ammonia in 320 parts water. The percentage composition is as below:

given are illustrative, not limiting, and that the formula-tion may be varied tosuitthe characteristics of the material to be treated, the environment in which the treated material is to be used, the nature of the most desired protection and, the availability of the various alternative materials. Thus, while all of the examples refer to the use of petroleum residues as bitumens, the use of wood tars, coal tars, and the products of both is contemplated. Except as regards volatility and cost, ammonia and the various low-boiling amines are equivalent and may be substituted at will. The relation of bitumen to toxic soap may be increased in cases where the most weight is placed on resistance to abrasion and weathering and decreased in cases where protection against bacterial action is of more importance.

In all formulae, however, the content of ammonia or amine must beatleast sumcientcto form the water-soluble complex with the toxic metal soap. Ihis quantity may readily be calculated from the combining weight of the selected metal by allowing one mol of ammonia for. each equivalent weight of the metal and in additionX mols of 'ammonla,-where X is the number of mols of ammonia required by each equivalent of the metal to form the ammonia complex. It is permissible to replace the ammonium oleate or stearate disclosed above as emulsifying agents with other emulsifiers known in the art. Sulfonated vegetable or petroleum oils, in the form of their ammonia or amine salts, are particularly recommended for that purpose.

Copper stearate; per cent 12.3 46.4 Asphalt -do 12.3 46.4 T-E-A stearate do 1.9 7.2 Ammonia as NH: do 2.7 Water do 70.8

water-miscible solvent, for example isopropyl alcohol or one of the butyl alcohols. By this means the 'emulsification can be brought about at normal temperaturesand the excessive loss of, am-" monia or volatile amine incurred in agitating at high temperature is avoided.

Example 6.Without adding soluble soap tion were liquefied by gentle heating and blended with 100 parts of a solution of copper naphthenate in isopropyl alcohol, this solution containing of the naphthenate'. This blend was then dispersed in a solution of parts 28% aqueous ammonia in 600 parts water, by agitation at atmospheric temperature. Percentage position:

It will be understood that the example above In the use of any of the above treating liquids the rope, twine, net or fabric is passed through a cold bath of the aqueous agent at such speed as to be saturated to the desired depth, after which it is drained and dried or allowed to dry. The ratio of bitumen to soap in the deposited film is controlled in the formulation of the treating liquid. The amount of bitumen soap deposited may to some extent be controlled by squeezing or centrifuging the saturated product as itemerges from the bath, by regulating the speed of passage through the bath and, with more exactness, by varying the concentration of the bath. Any of the above liquids may be diluted with water to any desired degree, adding ammonia or amine if necessary to replace evaporation and thus to maintain solubility of the soap. In draining back into the treating bath it will be remembered that bituminous emulsions break rapidly on contact with solid surfaces (the fibre surface) rather than by evaporation of the aqueous phase, whilemetallo-ammonium or amine complexes are resolved by evaporation of the amine constituent. It follows that the treating bath is more or less subject to progressive dilu- 0] tion and may need to be fortified from time to 100 parts petroleum road'oilof /180 penetratime by addition of a more concentrated liquid,

v particularly one richer in bitumen.

ammonia or a highly volatile amine, instability may beincident to the evaporation of ammonia or amine from the bath. This lost amine content should be replaced at intervals.

Whichever method of preparation of the treating liquid may be adopted,the passage of the fibrous article through the bath and the subsequent drying produce the deposition on the fibre surfaces of a smooth,,tough and pliable coating rich in bactericidal ingredients. The advantages of this general method as compared with the methods of theprior art may be summarized as follows: 1

a. The article treated is protected'to a very high degree against bacterial action, abrasion and the effects of sunlight;

b. Such articles as cordage are penetrated much more deeply and rapidly by the aqueous emulsion than by hot tar or other bitumen as such;

0. The shrinkage incident to treatment, is reduced to the order of 12% to 15% per dimension, materially less than that suffered in hot treatment;

d. As the treatment is performed in the cold, the deleterious effects of heat on the fibre are avoided;

e. The finished article is not tacky nor sticky but quite dry and easily handled, while on the other hand the stiffness of hot saturated products is avoided;

f. The weight increase due to the described treatment is usually about one-third that incident to hot saturation while at the same time to degree of protection afforded is materially increased.

g. The hydrolysis of the copper soap or other toxic metal soap is substantially inhibited by the presence of the bitumen and thus the bactericidal effect of the metal is preserved during a long period of use.

I claim as my invention:

1. A treating liquid for prolonging the life of articles composed substantiallyrof vegetable fibre consisting substantially of a suspension of a bitumen in an aqueous solution of a soap of a complex, ion formed of a bactericidal metal and a member of the group consisting of ammonia and the aliphatic amines boiling between about 15 and about C. the weight relation between said bitumen and said soap being within the range from 3:.1 to 1:3. I

2. A treating liquid for prolonging the life of articles composed substantially of vegetable fibre consisting substantially of bitumen intimately dispersed in an aqueous medium containing in solution an unstable compound cl a volatile alkaline agent with a soap oi a bactericidal metal, the weight relation between said soap and said bitumen being not less than one to three.

3. A treating liquid for prolonging the life of vegetable fibres composed substantially of an intimate dispersion of a bitumen in an aqueous solution of an alkaline agent selected from the group consisting of ammonia and the aliphatic amines boiling between about 15 and 100 C., together with a soap of a bactericidal metal, said soap being initially present solely in said aqueous solution.

4. The method of producing a treating liquid for prolonging the life of articles composed substantially of vegetable fibre, which comprises: dissolving a soap of a bactericidal metal in an aqueous solution of an alkaline agent selected from the group consisting of ammonia and the allphatic amines boiling between about 15 and about 100 C.,-and blending said solution with a previously prepared aqueous dispersion of a substantially soap-free bitumen. v

HAROLD scrum. 

